For the past 50 years, atomic standards based on the frequency of the cesium ground-state hyperfine transition have been the most accurate time pieces in the world. We now report a comparison between the cesium fountain standard NIST-F1, which has been evaluated with an inaccuracy of about 4×10-16, and an optical frequency standard based on an ultraviolet transition in a single, laser-cooled mercury ion for which the fractional systematic frequency uncertainty was below 7.2×10-17. The absolute frequency of the transition was measured versus cesium to be 1 064 721 609 899 144.94 (97) Hz, with a statistically limited total fractional uncertainty of 9.1×10-16, the most accurate absolute measurement of an optical frequency to date.
Single-Atom Optical Clock with High Accuracy / W. H., O., S. A., D., E. A., D., T. M., F., T. P., H., L., H., W. M., I., S. R., J., M. J., D., K., K., Levi, F., T. E., P., AND J. C., B.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 97:(2006). [10.1103/PhysRevLett.97.020801]
Single-Atom Optical Clock with High Accuracy
LEVI, FILIPPO;
2006
Abstract
For the past 50 years, atomic standards based on the frequency of the cesium ground-state hyperfine transition have been the most accurate time pieces in the world. We now report a comparison between the cesium fountain standard NIST-F1, which has been evaluated with an inaccuracy of about 4×10-16, and an optical frequency standard based on an ultraviolet transition in a single, laser-cooled mercury ion for which the fractional systematic frequency uncertainty was below 7.2×10-17. The absolute frequency of the transition was measured versus cesium to be 1 064 721 609 899 144.94 (97) Hz, with a statistically limited total fractional uncertainty of 9.1×10-16, the most accurate absolute measurement of an optical frequency to date.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
